LSI and Microprogramming

Microprogramming concepts were well known before LSI, however, with LSI, the impact of microprogramming techniques on computer architecture will increaes. Microprogramming was not used much until the advent of relatively low-cost ROS. It is already used extensively in many systems, including System/360 and System/370 for control store and emulation purposes.

大规模集成电路和微程序设计

虽然在大规模集成电路出现之前，微程序设计的概念已经是众所周知的了，但是，有了大规模集成电路，微程序设计技术对于计算机结构格式的影响将与日俱增。直到出现了成本比较低的只读存储器（ROS)之后微程序设计才用得多起来。现在它已广泛应用于许多计算机系统中，其中包括用于控制存储和仿真的360和370系统。

Well publicized attributes of microprogramming include ease of system design and change, greater flexibility and versatility, wider functional capability and improved performance in certain important areas. In addition, a system organization using microprogramming usually results in a more regular and repetitive hardware design (more than just the storage arrays) which is more amenable to LSI implementation.

LSI projections offer ROS at costs far below any here-to-date --- but more important, these projections can offer highspeed writable control stores (WCS) via RAM semiconductor memory at sufficiently low costs, as well. 

广为宜传的微程序设计的属性包括以下几点：容易进行系统设计与变换、灵活性与通用性更强、功能更齐全以及在某些重要的领域性能有所改善等。加之，使用微程序设计的系统结构通常会导致硬件设计更为整齐划一、规格一致（不仅仅是存储阵列)，这样就能更适合于实现大规模集成电路。

利用大规模集成电路的工程设计能以大大低于至今任何一种存储器的成本造出只读存储器（ROS)——更为重要的是，利用这些工程设计还能以足够低的成本通过半导体随机存储器（RAM)造出高速可写控制存储器(wCs)。

It is the LSI-afforded, dynamically writable control store which portends the most significant impact on future architecture --- and accounts for much of the growing current interest in "dynamic microprogramming". Advocates of microprogramming point to excessively complex software, the logical primitiveness of present computer hardware, and the large gap between machine and programming languages in present-day systems. The employment of microprogramming-enhanced design principles, problem-oriented (macro-oriented) instruction sets, and more complex machine language primitives, respectively, are suggested for the above problems. There are examples where factors of 20 and greater savings were achieved using microprogrammed problem-oriented macros, as compared with a typical general-purpose processor.

正是由大规模集成电路所提供的动态可写控制存储器才预示着它对未来的计算机格式会产生最重要的影响，也才说明了目前对于“动态微程序设计”的兴趣日益增加的主要原因.提倡微程序设计的人认为：软件过于复杂：目前计算机硬件在逻辑上较为原始；在现代系统中机器语盲与程序语言之间存在着很大的鸿沟。针对上述问题.他们提出分别使用由微程序设计所启发的设计原理、面向问题的（宏面向的）指令组以及更复杂的机器语言的原语等来解决。有一些使用了微程序设计的面向问题的宏指令的例子，它们同典型的通用处理机比较起来，成本就只有原来的二十分之一或更低。

Microprogramming techniques, exploiting the less sensitive cost-capacity relationships of semiconductor memory, facilitate conisideration of decentralized control. This allows a more compressed microcode and its execution in paralleled or pipelined fashion. Further, it is usually easier to design, analyze, and maintain smaller, decentralized programs. 

Opler projected the notion of a microprogramming region between software and hardware, dubbed "firmware," for fourthgeneration computers many years ago. Microprogramming techniques are presently being used in the industry in the areas of memory and file management, resource allocation, interrupt handling, recovery, and communication between processors in multiprocessing configurations. 

微程序设计技术由于利用了对成本-容量关系不太敏感的半导体存储器，所以便利了对局部控制的考虑。这就可能创造更为压缩的微程序代码并有可能以并行或流水线的方式来执行这种微程序代码。此外，设计、分析和维护比较短的局部程序通常也都比较容易。

许多年前，奥普勒就为第四代计算机提出了关于在软件与硬件之间建立叫做“固件”的微程序设计区域的概念。现在，微程序设计技术正在工业上用于如下几个领域：存储器管理与文件管理、资源分配、中断处理、复原以及在多边处理配置中处理机之间的通信等。

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